Improvement in insulators for telegraph-wires



J. I. CONKLlN, Jr.

improvement in Insulators for Telegraph-Wires.

N0.126,027, PatentedApril23,l872.

' o MzW; JAM/w a j mm;

UNITED STATES PATENT QFFIGE.

IMPROVEMENT IN INSULATORS FOR TEhEGRAPH-WIRES.

Specification forming part of Letters Patent No. 126,027, dated April23, 1872.

To all whom "it may concern:

Be it known that I, Josnrn I.GoNKL1N,Jr., of the city and State of NewYork, have invented an Improvement in Insulators for Tele graph-Wires,and the following is declared to be a correct description of the same.

The metal pin employed to connect the insulator to the post or cross-barhas been coated with a plastic non-conducting material, such as hardrubber. I make use of a pin so coated, but instead of being circular andscrewed into the glass, I make a tapering head flattened upon said metalpin, thereby obtaining greater strength, and enabling me to introduce awrapping of mica between the exterior of said pin and the interior of acorrespondingly-shaped hole in the vitrified insulator. I also introducea layer of mica between the end of the pin and a vitrified cap, that isapplied at the upper end of the insulator, and is cemented in place.

In the drawing, Figure 1 is a vertical section of the said insulator.Fig. 2 is a similar view at right angles to Fig. 1, and Fig. 3 is aninverted plan of the insulator.

The pin a is made with a tapering enlargement or head, I), and is coatedwith non-conducting material c, in which is a screw-thread for holdingthe pin in the hole of the cross-bar or post at. The insulator glass ismade in two parts, the body 6 has a hole through it of a size to receivethe head b of the pin, together with a wrapping of mica to render theinsulation more perfect. It is preferable that the head I) should beflattened on two sides, as

shown, so as to prevent turning, and at the same time less material willbe used. The body of this insulator e is grooved at f, for receiving thewire and attachment g, and this being nearly in the middle of theinsulator,

there is no undue strain or leverage either on the pin or the insulatorby the tension of the telegraph-wire.

The mica insulator is confined between the glass and the pin undercircumstances where it cannot be broken or work loose. At the end of thepin a I introduce a layer of mica, and then insert the dovetail l of thecap on into a dovetail groove in the upper part of the body e, andsecure the parts together by suitable cement.

The insulator made in this manner is much more perfect than thoseheretofore used, be- 5 J. I. CONKLIN, JR.

Witnesses:

GEO. T. PINCKNEY, Guns. H. SMITH.

